Modulation of epileptic networks by transient interictal epileptic activity: A dynamic approach to simultaneous EEG-fMRI.

Epileptic networks, defined as brain regions involved in epileptic brain activity, have been mapped by functional connectivity in simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) recordings. This technique allows to define brain hemodynamic changes, measured by the Blood Oxygen Level Dependent (BOLD) signal, associated to the interictal epileptic discharges (IED), which together with ictal events constitute a signature of epileptic disease. Given the highly time-varying nature of epileptic activity, a dynamic functional connectivity (dFC) analysis of EEG-fMRI data appears particularly suitable, having the potential to identify transitory features of specific connections in epileptic networks. In the present study, we propose a novel method, defined dFC-EEG, that integrates dFC assessed by fMRI with the information recorded by simultaneous scalp EEG, in order to identify the connections characterised by a dynamic profile correlated with the occurrence of IED, forming the dynamic epileptic subnetwork. Ten patients with drug-resistant focal epilepsy were included, with different aetiology and showing a widespread (or multilobar) BOLD activation, defined as involving at least two distinct clusters, located in two different lobes and/or extended to the hemisphere contralateral to the epileptic focus. The epileptic focus was defined from the IED-related BOLD map. Regions involved in the occurrence of interictal epileptic activity; i.e., forming the epileptic network, were identified by a general linear model considering the timecourse of the fMRI-defined focus as main regressor. dFC between these regions was assessed with a sliding-window approach. dFC timecourses were then correlated with the sliding-window variance of the IED signal (VarIED), to identify connections whose dynamics related to the epileptic activity; i.e., the dynamic epileptic subnetwork. As expected, given the very different clinical picture of each individual, the extent of this subnetwork was highly variable across patients, but was but was reduced of at least 30% with respect to the initially identified epileptic network in 9/10 patients. The connections of the dynamic subnetwork were most commonly close to the epileptic focus, as reflected by the laterality index of the subnetwork connections, reported higher than the one within the original epileptic network. Moreover, the correlation between dFC timecourses and VarIED was predominantly positive, suggesting a strengthening of the dynamic subnetwork associated to the occurrence of IED. The integration of dFC and scalp IED offers a more specific description of the epileptic network, identifying connections strongly influenced by IED. These findings could be relevant in the pre-surgical evaluation for the resection or disconnection of the epileptogenic zone and help in reaching a better post-surgical outcome. This would be particularly important for patients characterised by a widespread pathological brain activity which challenges the surgical intervention.

The network integration of epileptic activity in relation to surgical outcome.

OBJECTIVE: Epilepsy is a network disease with epileptic activity and cognitive impairment involving large-scale brain networks. A complex network is involved in the seizure and in the interictal epileptiform discharges (IEDs). Directed connectivity analysis, describing the information transfer between brain regions, and graph analysis are applied to high-density EEG to characterise networks. METHODS: We analysed 19 patients with focal epilepsy who had high-density EEG containing IED and underwent surgery. We estimated cortical activity during IED using electric source analysis in 72 atlas-based cortical regions of the individual brain MRI. We applied directed connectivity analysis (information Partial Directed Coherence) and graph analysis on these sources and compared patients with good vs poor post-operative outcome at global, hemispheric and lobar level. RESULTS: We found lower network integration reflected by global, hemispheric, lobar efficiency during the IED (p < 0.05) in patients with good post-surgical outcome, compared to patients with poor outcome. Prediction was better than using the IED field or the localisation obtained by electric source imaging. CONCLUSIONS: Abnormal network patterns in epilepsy are related to seizure outcome after surgery. SIGNIFICANCE: Our finding may help understand networks related to a more "isolated" epileptic activity, limiting the extent of the epileptic network in patients with subsequent good post-operative outcome.

Uneven Linguistic Outcome in Extremely Preterm Children.

One primary problem in extremely preterm children is the occurrence of atypical language development. The aim of this study was to explore the components of language (articulatory phonetics, lexicon and syntax) in comprehension and production in extremely preterm children between the 4th and 5th year of age. The language section of the Preschool Neuropsychological Test was administered to 20 extremely preterm monolingual Italian children (GA < 28 weeks) and to a control sample of 40 full term children (GA > 37 weeks), matched for age and non-verbal IQ. Language comprehension was fully efficient in all of the components that we assessed. In the tasks of language production the clinical sample fared much worse than their age and IQ matched controls and the differences were highly significant (p < .001). Language acquisition in extremely preterm children may follow uneven developmental trajectories: language comprehension can be spared in the face of a selective impairment of language production at the level of articulatory phonetics and syntax.

Decision-making in adult thalassemia patients undergoing unrelated bone marrow transplantation: quality of life, communication and ethical issues.

Bone marrow transplantation (BMT) represents a potentially curative treatment of thalassemia. For patients without an HLA-identical sibling donor, recourse to an unrelated donor is a practicable option but the candidates and their families are faced with a difficult decision. They can either choose to continue the supportive therapy, with no chance of definitive cure, or they accept the mortality risk of BMT in the hope of obtaining a definitive resolution of the disease. We investigated the communication strategies and the post transplantation quality of life (QoL) in 19 adult thalassemia patients surviving after an unrelated donor BMT. The patients were given two questionnaires: a questionnaire to evaluate pre-transplantation communication factors and the EORTC QLQ-C30 questionnaire to assess global QoL. All patients were satisfied with the communication modalities employed by the physicians. The global post transplantation QoL in our patient cohort was found to be good. The approach used in this study may offer a contribution to understanding the decision-making process leading to the choice of a treatment with a high mortality risk for a chronic, non-malignant disease. Finally, some ethical issues of this therapeutic approach are briefly addressed.

Survival and complications in thalassemia.

The life expectancy of patients with thalassemia major has significantly increased in recent years, as reported by several groups in different countries. However, complications are still frequent and affect the patients' quality of life. In a recent study from the United Kingdom, it was found that 50% of the patients had died before age 35. At that age, 65% of the patients from an Italian long-term study were still alive. Heart disease is responsible for more than half of the deaths. The prevalence of complications in Italian patients born after 1970 includes heart failure in 7%, hypogonadism in 55%, hypothyroidism in 11%, and diabetes in 6%. Similar data were reported in patients from the United States. In the Italian study, lower ferritin levels were associated with a lower probability of experiencing heart failure and with prolonged survival. Osteoporosis and osteopenia are common and affect virtually all patients. Hepatitis C virus antibodies are present in 85% of multitransfused Italian patients, 23% of patients in the United Kingdom, 35% in the United States, 34% in France, and 21% in India. Hepatocellular carcinoma can complicate the course of hepatitis. A survey of Italian centers has identified 23 such cases in patients with a thalassemia syndrome. In conclusion, rates of survival and complication-free survival continue to improve, due to better treatment strategies. New complications are appearing in long-term survivors. Iron overload of the heart remains the main cause of morbidity and mortality.

Treatment and long-term results in children with acute myeloid leukaemia treated according to the AIEOP AML protocols.

Since 1982, four consecutive studies on childhood acute myeloid leukaemia (AML) (namely LAM-82, -87, -87M and -92) have been conducted in Italy by the Associazione Italiana di Ematologia e Oncologia Pediatrica (AIEOP) group. The induction therapy of the first three studies consisted of daunorubicin and cytarabine structured in a 3+7 backbone. In the most recent protocol (LAM92), patients received two induction courses including idarubicin, cytarabine and etoposide. Patients with acute promyelocytic leukaemia (20% of diagnoses) were included in LAM-87 and 87M studies. Postremissional therapy significantly changed over time, with an ever-increasing role given to stem cell transplantation (SCT). The long-term outcome of patients enrolled in the LAM-82, 87 and 87M studies was comparable, whereas that of children treated according to LAM-92 study was significantly better (P<0.005). Either allogeneic or autologous SCT was employed as consolidation therapy in more than 75% of cases enrolled in this latter study. Patients enrolled in the LAM-92 study were stratified in standard and high-risk groups with different outcome (67 vs 47%, respectively, P=0.04). Altogether, the results obtained in these four studies have permitted a progressive refinement of treatment, contributing to the structure of the ongoing LAM-2002 protocol that stratifies patients according to the presence of definite genetic anomalies and response to induction therapy.

Successful T-cell-depleted, related haploidentical peripheral blood stem cell transplantation in a patient with Fanconi anaemia using a fludarabine-based preparative regimen without radiation.

Haematopoietic stem cell transplantation (HSCT) represents the treatment of choice for severe bone marrow failure in patients with Fanconi anaemia (FA). When the donor is a compatible relative, the chance of being cured with an allograft is in the order of 70%. However, for FA children lacking an HLA-identical sibling, the results of HSCT from an alternative donor are less satisfactory because of a higher risk of graft rejection, graft-versus-host-disease (GVHD) and regimen-related toxicity. We report on a 12-year-old girl with FA, who was treated by T-cell-depleted (TCD) peripheral blood HSCT from her haploidentical uncle, using a novel fludarabine-based preparative regimen without radiation. She had rapid engraftment with no toxicity and no GVHD. Progressive recovery of both numbers of lymphocyte and of proliferative response to polyclonal activators occurred over time. At 18 months after transplantation, she is well with 100% donor chimerism and has recovered normal immune function.

Unrelated bone marrow transplantation in thalassemia. The experience of the Italian Bone Marrow Transplant Group (GITMO).

BACKGROUND AND OBJECTIVES: Allogeneic bone marrow transplantation (BMT) is a widely accepted therapeutic approach in homozygous beta-thalassemia. However, the majority of patients do not have a genotypically identical donor within the family. This prompted us to conduct a pilot study to investigate the feasibility of matched unrelated bone marrow transplantation in thalassemia. The major drawback was the high risk of immunologic and transplant-related complications, mainly graft-versus-host disease (GvHD) and graft failure. DESIGN AND METHODS: Our aim was to reduce this risk through careful selection of donor/recipient pairs. HLA haplotypes that show a high linkage disequilibrium among their class I, class II and class III alleles are considered extended or ancestral haplotypes. RESULTS: These haplotypes are conserved and can be shared by apparently unrelated individuals. Our study shows that matching for these haplotypes significantly improves the outcome of unrelated bone marrow transplantation in thalassemia. In fact, results were comparable to those obtained in transplants using HLA-identifical family donors. INTERPRETATION AND CONCLUSIONS: Better results were obtained in patients with lesser iron overload and when the donor shared an identity for the DPB1 alleles.

Anti-CD20 monoclonal antibody for the treatment of severe, immune-mediated, pure red cell aplasia and hemolytic anemia.

Immune-mediated, acquired pure red cell aplasia (PRCA) is a rare disorder frequently associated with other autoimmune phenomena. Conventional immunosuppressive treatment is often unsatisfactory. Rituximab is a monoclonal antibody against the CD20 antigen, highly effective for in vivo B-cell depletion. An 18-month-old girl with both severe PRCA and autoimmune hemolytic anemia, refractory to immunosuppressive treatment, received 2 doses of rituximab, 375 mg/m(2) per week. The drug was well tolerated. After anti-CD20 therapy, substitutive treatment with intravenous immunoglobulin was started. The treatment resulted in marked depletion of B cells; a striking rise in reticulocyte count ensued, with increasing hemoglobin levels, finally leading to transfusion independence. The child is now 5 months off-therapy, with normal hemoglobin and reticulocyte levels. This case suggests a role of anti-CD20 monoclonal antibody for treatment of patients with antibody-mediated hematologic disorders. (Blood. 2001;97:3995-3997)

Total-body irradiation and melphalan is a safe and effective conditioning regimen for autologous bone marrow transplantation in children with acute myeloid leukemia in first remission. The Italian Association for Pediatric Hematology and Oncology-Bone Marrow Transplantation Group.

PURPOSE: To evaluate the safety and efficacy of a preparative regimen consisting of fractionated total-body radiation (9.9 to 12 Gy) and melphalan (140 mg/m(2) in a single dose) in children with acute myeloid leukemia in first complete remission (CR) given autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: Fifty-three children (30 males and 23 females; age range, 1.5 to 18 years) were enrolled onto the study. The median time from first CR to ABMT was 3.5 months (range, 1.4 to 13 months), with 45 patients (85%) undergoing transplantation within 6 months from the diagnosis. Forty-five patients received in vitro marrow purging with standard-dose mafosfamide (100 microg/mL), seven patients were treated with interleukin-2 before marrow collection, and in the remaining child, the marrow was unmanipulated. The median infused cell dose was 1.8 x 10(8)/kg (range, 0.4 to 5.8 x 10(8)/kg). RESULTS: All patients but one achieved hematopoietic engraftment, with a median time to neutrophil recovery of 24 days (range,11 to 66 days). Treatment-related toxicity was moderate and consisted mainly of mucositis. One patient died from cytomegalovirus interstitial pneumonia, and one died from pulmonary hemorrhage. Fourteen patients (26%) relapsed at a median time of 6 months after ABMT (range, 2 to 17 months), with a cumulative relapse probability of 29% (95% confidence interval, 16% to 42%). The 5-year Kaplan-Meier estimate of survival for all 53 patients was 78% (range, 65% to 90%), whereas the overall 5-year disease-free survival was 68% (range, 55% to 81%), with a median follow-up duration of 40 months (range, 7 to 130 months). CONCLUSIONS: These data suggest that, in our cohort of patients, the combination of total-body irradiation and melphalan is safe and associated with good antileukemia activity, making ABMT an appealing alternative for postremission therapy in children with acute myeloid leukemia in first CR.

Resolution of immune haemolytic anaemia with allogeneic bone marrow transplantation after an unsuccessful autograft.

Autologous transplantation of lymphocyte-depleted peripheral blood stem cells (PBSC) has been proposed for treatment of patients with severe autoimmune disease. However, several patients have been reported to achieve only transient remissions. We report on a child with thalassaemia intermedia and immune-mediated haemolytic anaemia, given an autologous lymphocyte-depleted PBSC transplant, who relapsed 7 weeks after transplant. A complete remission, lasting 18 months to date, was obtained with allogeneic bone marrow transplantation (BMT) from an HLA-matched unrelated donor. This experience indicates that, in selected cases, allogeneic BMT may be the treatment of choice for life-threatening autoimmune disease. A graft-versus-autoimmunity effect may favour the eradication of the recipient autoaggressive lymphocytes.

[Mechanical reconstruction after total gastrectomy. Analysis of results]. / Ricostruzione meccanica dopo gastrectomia totale. Analisi dei risultati.

BACKGROUND: Stapling devices introduction in gastroesophageal surgery has allowed better results. METHODS: An analysis is made of a consecutive series of 108 patients operated on with total gastrectomy and mechanical esophagojejunostomy for gastric neoplasm, in the last decade (1984-1995). RESULTS: The incidence of anastomotic clinical leakage was 2.4% with a perioperative mortality of 0.9% (1 patient) while the incidence of stenosis, treated in every patient with endoscopic dilatation, was 3.2%. These data are in accordance with previous reports. After an accurate analysis of the factors influencing the complication rate pointed out that in most of the cases a technical error in the anastomosis confection is present. CONCLUSIONS: The conclusion is drawn that the use of stapling devices in gastroesophageal surgery represents an elective indication. Nevertheless it is mandatory to respect the principles of visceral mechanical anastomosis after an adequate training.

Mobilization and selection of peripheral blood hematopoietic progenitors in children with systemic sclerosis.

BACKGROUND AND OBJECTIVE: Autologous transplant of lymphocyte-depleted peripheral blood stem cells has been proposed for treatment of patients with severe autoimmune disease. However, until now, no data are available on the safety and feasibility of both stem cell collection and selection in pediatric patients with these disorders. We report on three children affected by systemic sclerosis with lung involvement, who received chemotherapy and granulocyte colony-stimulating factor (G-CSF) to mobilize autologous peripheral blood progenitors. DESIGN AND METHODS: The priming regimen consisted of cyclophosphamide (CY, 4 g/m(2)) and G-CSF (lenograstim, 10 microg/kg/day starting 2 days after cyclophosphamide administration until stem cell collection). Leukapheresis was performed when WBC and CD34+ cell count were at least 2 x 10(9)/L and 0.03 x 10(9)/L, respectively. In the first patient, positive selection of CD34+ cells was performed through the Ceprate SC stem cell concentrator (CellPro, Bothell, WA, USA). In the remaining 2 children, progenitor cells were also purged with negative selection of CD4+ and CD8+ lymphocytes performed by means of the Isolex 300i device (Baxter). RESULTS: All patients tolerated the priming regimen well and did not present any sign of autoimmune disease exacerbation. Collection was successful in all children and the number of CD34+ cells before selection ranged between 10.7 x 10(6) and 17.6 x 10(6)/kg of patient body weight. The selection of haematopoietic stem cells in the 3 patients resulted in at least 2. 6-log T-cell depletion of the cell content, with a recovery of the initial value of CD34+ cells comprised between 21 and 44%. After, a preparative regimen consisting of CY (200 mg/kg over 4 days) and Campath-1 G in vivo (10 mg/day for 2 consecutive days), patients were transplanted using cryopreserved lymphocyte-depleted progenitor cells. In all cases, a prompt hematopoietic engraftment was observed. INTERPRETATION AND CONCLUSIONS: Taken together these data suggest that mobilization, collection and selection of hematopoietic progenitors are safe and feasible in children with autoimmune disease.

The haemochromatosis mutations do not modify the clinical picture of thalassaemia major in patients regularly transfused and chelated.

Iron overload is the main cause of morbidity and mortality in patients with thalassaemia major. In order to establish if the presence of the mutations recently described in the haemochromatosis gene affects the severity of iron overload in thalassaemia patients, we compared the prevalence of mutations C282Y and H63D in 216 young adults regularly transfused and chelated in North-Eastern Italy with the frequency found in a group of blood donors from the same area. For each patient, mean serum ferritin over the last 3 years, liver iron concentration, and the presence of diabetes, hypogonadism and heart disease, were considered. The frequency of the C282Y allele was 1.9% in patients with thalassaemia major and 2.3% in blood donors (P=ns). The frequency of the H63D allele was 16.2% in patients with thalassaemia major and 15.3% in blood donors (P=ns). When age, liver iron concentration and mean yearly serum ferritin levels were compared in patients with and without mutations C282Y and H63D, no significant differences were found. Also, the prevalence of iron-induced complications was not significantly different between patients carrying or not carrying the mutations. The presence of the HH mutations does not seem to influence the degree of iron overload and its consequences in regularly transfused and chelated patients with thalassaemia major.

Survival and disease complications in thalassemia major.

We studied survival and disease complications in 1,146 patients with thalassemia major, born from January 1, 1960 to December 31, 1987. At last follow-up, in March 1997, probability of survival to age 20 years was 89% and to age 25 years was 82% for patients born in the years 1970-1974. Patients who died had a serum ferritin level, measured the year before death, significantly higher than those who survived. Diabetes was present in 5.4% of the patients; heart failure in 6.4%; arrhythmias in 5.0%, thrombosis in 1.1%, hypothyroidism in 11.6%, HIV infection in 1.8%. Hypogonadism was diagnosed in 55% of 578 patients who had reached pubertal age: 83.5% of hypogonadic females and 78.6% of males were receiving substitutive hormonal therapy. In conclusion, the survival of patients with thalassemia major is good and improving, but the prevalence of severe complications is still high.

A moderate transfusion regimen may reduce iron loading in beta-thalassemia major without producing excessive expansion of erythropoiesis.

BACKGROUND: Hypertransfusion with a baseline hemoglobin of 10 to 12 g per dL is still considered by many to be the mainstay of conservative therapy for beta-thalassemia major. However, this regimen is frequently associated with manifestations of transfusion iron overload, despite regular chelation therapy with subcutaneous desferoxamine. STUDY DESIGN AND METHODS: To verify whether a transfusion regimen with a target pretransfusion hemoglobin level between 9 and 10 g per dL can allow a significant reduction in blood consumption, while still effectively suppressing erythropoiesis, the records were reviewed of 32 beta-thalassemia major patients, who were maintained at a pretransfusion hemoglobin of 11.3 +/- 0.5 g per dL between 1981 and 1986. These patients were switched at the beginning of 1987 to a transfusion regimen with pretransfusion hemoglobin of 9.4 +/- 0.4 g per dL. The degree of erythroid marrow activity was evaluated in these patients and in 32 subjects with beta-thalassemia intermedia through the simple measurement of serum transferrin receptor. RESULTS: After the adoption of the moderate transfusion regimen, transfusion requirements decreased from 137 +/- 26 to 104 +/- 23 mL per kg per year of red cells (p < 0.0001), and mean serum ferritin decreased from 2448 +/- 1515 to 1187 +/- 816 micrograms per L (p < 0.0001), with one-half of patients achieving serum ferritin levels lower than 1000 micrograms per L. The proportion of patients having spontaneous pubertal development increased significantly (p < 0.01), as a result of less iron-related gonadotropin insufficiency. At the lower pretransfusion hemoglobin, erythroid marrow activity did not exceed two to three times normal levels in most subjects. CONCLUSION: As compared with hypertransfusion, moderate transfusion may allow more effective prevention of iron loading, with higher likelihood of spontaneous pubertal development and without producing excessive expansion of erythropoiesis.

A trial of high-dose dexamethasone therapy for chronic idiopathic thrombocytopenic purpura in childhood.

OBJECTIVE: To determine the efficacy of high-dose dexamethasone in chronic idiopathic thrombocytopenic purpura of childhood. METHODS: Seventeen patients entered the protocol. Dexamethasone was to be given orally in two divided doses at a dosage of 20 mg/m2 for 4 consecutive days every 28 days for six courses. RESULTS: One month after the end of the sixth course, six patients (35%) had platelet values within the normal range. One year later, five patients (29%) still have normal platelet values. Five patients discontinued treatment before completion because of lack of response and in one case for important side effects. Duration of the disease before treatment was inversely correlated with response to dexamethasone: 5 of 10 patients who had had thrombocytopenia for 30 months or less went into remission, as opposed to none of the seven who had been sick for a longer period (p = 0.04). Side effects included fatigue or irritability, anxiety, abdominal pain, striae, hirsutism, acne, and weight gain. CONCLUSIONS: Contrary to what is observed in adults, in our patients pulsed dexamethasone therapy did not prove to be uniformly effective. However, in view of its effectiveness in a third of the patients, acceptable side effects, and low cost, we believe that this treatment could be considered in patients with chronic idiopathic thrombocytopenic purpura who do not tolerate the disease well, especially if no more than 3 years have elapsed since diagnosis. Larger studies will be necessary to define which patients will respond to this type of therapy.

Hematopoietic and immune recovery after transplantation of cord blood progenitor cells in children.

Matched related cord blood transplantation (CBT) has been successfully used to rescue patients undergoing myeloablative therapy. However, few data are available on the kinetics of hematological and immunological reconstitution of CBT recipients. We have investigated the hematological engraftment and immune recovery following related CBT in three patients, with acute lymphoblastic leukemia, aged 10, 9 and 7 years and with a body weight of 31, 40 and 25 kg, respectively. All patients engrafted and none experienced acute or chronic graft-versus-host disease. The time needed to achieve granulocyte recovery was 13, 26 and 29 days, respectively and platelet recovery occurred in 28, 49 and 51 days. All patients presented a marked increase of HbF, the values observed being much greater than those documented in patients given marrow transplantation and comparable with those observed in normal children in the first year of age. The recovery of T cell immunity, as well as that of natural killer subpopulations, mimicked that described in BMT recipients, a quicker return of CD8+ T cells determining the characteristic inversion of CD4/CD8 ratio. An impressive increase in the percentage and absolute number of B lymphocytes, apparently not related to viral infections, was demonstrable in all three cases. These data suggest that CBT recipients can experience a slight delay in hematological recovery when compared with patients given BMT. The reconstitution of erythropoiesis seems to recapitulate the ontogenetic pattern and the kinetics of recovery of the immune system reproduce that observed after BMT with the peculiarity of B cell expansion in peripheral blood.

Frequency of donor cytotoxic T cell precursors does not correlate with occurrence of acute graft-versus-host disease in children transplanted using unrelated donors.

Bone marrow transplantation (BMT) from unrelated volunteers is frequently associated with both increased incidence and increased severity of acute graft-versus-host disease (GVHD). In the last years, it has been suggested that the analysis of the frequency of cytotoxic T lymphocyte precursors (CTLp) of unrelated HLA-matched donors can be used to detect disparity for HLA class I antigens and as a predictive test for development of severe GVHD. In this report, we summarized our experience regarding 20 pediatric patients affected by various hematological disorders, receiving allogeneic BMT from unrelated donors. HLA class I and II antigens of donor/recipient pairs were determined by means of serological typing, whereas molecular typing of HLA-class II antigens of patients and their potential donors was performed using PCR-SSP and PCR-fingerprinting techniques. CTLp values, estimated using limiting dilution analysis, were high (range, 1:7000-1:40,000) in 9 of 20 patients, while the other 11 children had low or undetectable levels (< 1:100,000) of CTL precursors. CTLp frequency was compared with the incidence and severity of GVHD observed after BMT. Our data demonstrate that the frequency of donor CTLp does not statistically correlate either with the occurrence of clinically significant acute GVHD or with disparity for HLA-class II molecular typing between donor and recipient. In particular, 4 of the 10 evaluable patients with an undetectable CTLp frequency developed grade IV, III, II, and IV acute GVHD, respectively. Although the limited number of subjects studied does not allow us to draw any firm conclusion, our data suggest a certain caution in considering this test suitable for the selection of potential donors.

Role of allogeneic bone marrow transplantation from an HLA-identical sibling or a matched unrelated donor in the treatment of children with juvenile chronic myeloid leukaemia.

Seven children (age range 1.8-11 years) with juvenile chronic myelomonocytic leukaemia (JCML) received an allogeneic bone marrow transplantation (BMT), four from an HLA-identical sibling and three from a matched unrelated donor. In the four children transplanted using an HLA-identical sibling, conditioning regimen included busulfan (BU), cyclophosphamide (CY) and melphalan (L-PAM), whereas graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine-A (Cs-A). The preparative regimen was well tolerated and all patients engrafted promptly. None of the patients have relapsed and all four children remain in haematological remission after an observation time of 7, 24, 25 and 48 months, respectively. Of the three children given BMT from an unrelated volunteer, one was < 2 years of age and she received the BU/CY/L-PAM regimen. In view of the increased risk of graft rejection described in patients transplanted from unrelated donors, we chose to prepare the other two patients with fractionated total body irradiation (TBI), thiotepa and CY. Cs-A, short-term methotrexate and Campath-1G in vivo were employed to prevent GVHD in this group of patients. Graft failure with autologous reconstitution of haemopoiesis occurred in the child given the chemotherapy-based regimen. One of the two girls given TBI relapsed after BMT; therefore only one of the three patients who received a marrow transplant from a matched unrelated donor survives in complete haematological remission 10 months after BMT. Our study suggests that the conditioning regimen we employed for allogeneic BMT from a compatible sibling is an effective means of eradicating the leukaemic clone. In our experience, results obtained using unrelated donors are less satisfactory and, at present, the use of such donors seems to be riskier and associated with a lower success rate as compared with BMT from an HLA-identical sibling.